1. Field of the Invention
The present invention relates to a display apparatus having a plurality of display panels (i.e., a plurality of display areas).
2. Description of the Related Art
As the conventional technologies, in U.S. patent application Publication No. 2001/0052887(JP-A-2001-356746), a partial display has been described, which performs a display in a partial area on the display panel. Namely, in U.S. patent application Publication No. 2001/0052887, when a partial display instruction is issued in the driving of a display apparatus such as a liquid-crystal display apparatus equipped with pixels of an n-row×m-column matrix, the partial display is performed, as follows: During one frame time-period, the respective rows of a settable s-row×m-column partial display area are sequentially selected out of the n-row×m-column matrix, then writing predetermined partial display data into the respective rows. Moreover, predetermined background display data such as off-display (i.e., white-display) data is written into a background area which is the remainder of the partial display area. At this time, only a k-row×m-column background area is selected during the one frame time-period, then writing the background display data therein. The k rows to be selected are shift-processed on each frame basis, and the entire background area is selected once during the time-period of (n-s)/k frames. The writing-in of the background display data is performed in such a manner that the polarity with respect to a reference voltage is inverted on each predetermined time-period basis. This allows the pixels in the background area to be securely inversion-driven with the off-display data. In U.S. patent application Publication No. 2001/0052887, however, no description has been given concerning the driving of two display panels.
Also, in U.S. Pat. No. 6,396,469 (JP-A-11-109921), a display apparatus has been disclosed, which drives two pixel arrays independently of each other by using different data drivers. Namely, in U.S. Pat. No. 6,396,469, there is provided the following control unit: In order to display an image on the liquid-crystal panel in one time-period within a period during which one image is displayed, the control unit controls a gate-line driving unit so that a gate line will be selected for each of the first and second pixel arrays, and controls the first and second data drivers so that an image signal for displaying the image will be supplied to first and second data-line groups. In addition, in another time-period included within the same period as that of the one time-period and differing from the one time-period, the control unit controls the gate-line driving unit so that the gate line will be selected again for each of the first and second pixel arrays, and controls the first and second data drivers so that a non-image signal, which has a predetermined electric potential and differs from the image signal, will be supplied to the first and second data-line groups. In U.S. Pat. No. 6,396,469, however, no description has been given concerning the driving of the two pixel arrays by using the one data driver.
Also, in U.S. Pat. No. 5,670,970 (JP-A-07-175448), the disclosure has been made regarding the driving of two liquid-crystal panels by using one driver. Namely, in U.S. Pat. No. 5,670,970, there are provided the XY-matrix-type first and second liquid-crystal panels which have a switching element and a storage element on each pixel basis, and a liquid-crystal driving apparatus. Here, this liquid-crystal driving apparatus supplies the first and second liquid-crystal panels with an image signal whose polarity is inverted on each predetermined period basis, so that polarities of the image signals simultaneously supplied to the first and second liquid-crystal panels will become mutually opposite polarities. In U.S. Pat. No. 5,670,970, however, no description has been given concerning the feeding of different image signals to the two liquid-crystal panels.